Tubular electric discharge lamp unit



Jan. 8, 1952 E. MANN 2,581,546

TUBULAR ELECTRIC DISCHARGE LAMP UNIT Filed April 27, 1946 INVENTOR:

ERNO MANN,

HIS ATTORNEY Patented Jan. 8, 1952 TUBULAR ELECTRIC DISCHARGE LAMP UNIT Ernii- Mann, Eindhoven,Netherlands,. assignor, by mesneassignments, to Hartford. National Bank. and; Trust Company, as trustee Application April 27, 1946, Serial No. 665,398 In the Netherlands October 29; 1942 Section 1, Public Law 6911', August 8, 1946 Patentexpires October 29, 1962 2 Claims.

to a device comprising a instalment of the tube must be effected by means of two tube holders; Apart from the instalment of the auxiliary appliances for the ignition and the operation of such a tube the instalment of the device requires the laying of current leads between the twotube holders; forthis purpose the wall to which the tube issecured for example has formed in itbetween the tube holders a channel in which the current leads are housed.

The invention has for its object to simplify the instalment of the tube.

According to the invention, one: of the tube holders'is arranged. to be connected to a source or current and the conductors that connect the other tube holder to the tube holder capable of being. connected are united with: the discharge tube toform a singleunit. Consequently, there is no need for current. leads to be arranged between the two tube holders in or on. the wall or other base on which the tube is installed; the electric" connection between the two tube holders is established; on the discharge tube being introduced. into the holders. The instalment of the deviceis, thusmuch simplified. A further simplificationris ensured if. all the auxiliary devices or equipment necessary for the ignition and opera-- tion of. they tube or part of them are housed in either of the tube holders or in both. The dis-' charge tube to be. used in such a device is characterized in that it contains at least one conductor which is connected to two contact members placed at different ends of the tube and which is insulated with respect to at least one of theelectrodes offthe tube.

In-order that invention may be clearly understood. andreadily carried into effectit will now be. described. more fully with reference to the accompanying. drawing, in which two embodiments are diagrammatically shown.

The device shown in Figure. 1 contains a luminous. elongated straight discharge tube or lamp l whichmay be for. examplaa low-pressure mercury-vapour discharge tube, whose tube wall is: internally coated with powder that becomes luminescent under the action of the. rays generated in. the discharge; The tube i comprises incandescent electrodes 2 and 3 placed respectively at the ends and two conductors 4 and 5 placed in position along the exterior of the wall. The tube ends are covered by two caps 6 and 1 which are attached to the tube for example by cemeting and are provided with: several contact members. The conductor 5 is connected to the contact member 9' of the cap 1 and is otherwise connected through the incandescent electrode 2 to the contact member 8 of the cap 6. Similarly, the conductor 4 is connected. to the contactmembeer I lof the capli and on the other hand. through the incandescentelectrode 3 to the contact memberlllot the cap 1.

The cap 6 is held. in a lamp-holder l2 providedwith contact members. [3 and M, which correspond, with the. contact members H and 8 of the cap 6.. The cap 1 is held. in the lamp-holder [5. This. lamp-holder is. provided. with two contact members l6 and. H, which make contact with the members I0 and 9 of the cap 1. For simplicity the construction of the caps and lamp-holders is not shown in detail in Figure 1. and the contact members of the caps as well as those of the lampholders are shown slightly spaced. apart. By means of two" conductors leading to the contact members I3 and it" the lamp-holder- I2 is connected toa small box I8 containing a choke coil I91 The box IE is provided in addition with two connecting members or terminals 20 and 21' for connection to a source of current, for example an alternating-current supply of 220 volts and 50 cycles; The holder l5 contains a switch 22, for example a small glbw-discharge tube having at least one electrode fitted on abimetallic strip, and a condenser 23 connected in parallel therewith. The currentinterruptor 22. and the condenser 23 mayalsobe arranged externally of the holder l5.

On the device being put under tension and the switch 22 being closed a heavy current passes through the choke coil l5, the contacts l3 and H, the: conductor 4, the electrode 3, the contacts It and lit, the switch: 22, the contacts I! and 9, the conductor 5, theelectrode 2 and the contacts- 8 and M This makes. the electrodes 2 and 3 rapidly assume theemission temperature; after. this the switch interrupts the connection between the. electrodes in, a well-known manner so that the tube can be started up and this is assisted by a voltage pulse which. on interruption or the" 3 circuit is supplied by the choke coil 3. The condenser 23 acts as a radio-interference neutralizin member.

The lamp-holders l2 and I5 are secured for example to the wall of a living room. The box 18 is housed as usual in the wall, preferably in the proximity of the lamp-holder l2. As may be clearly seen, there is no electric connection external of the tube between the widely spaced lamp-holders l2 and I5 so that there is no need for the latter to be placed in the wall or in an insulating tube that disfigures the room.

The caps 6 and 1 are symmetrical and identical so that in installing the tube in the holders there is no need to have regard to a definite position of the tube: the tube may unobjectionally be rotated by 180 about its longitudinal axis and the cap 6 may also be inserted in the holder l5 and the cap I in the holder l2. In doin so, the conductors 4 and 5 may be so secured to the tube as to be placed laterally of the tube when the latter is introduced into the holders. The attachment of the conductors 4 and 5 to the tube wall may be effected for example by means of a glass having a low melting point or a synthetic resin, preferably transparent, and so forth. It is thus possible to reduce the loss of light to a negligible value. The instalment of the conductors 4 and 5 may be efiected prior to the; application of the luminescent layer in the tube so that during any heat treatment that may be necessary during the instalment of the conductors 4 and 5 the luminescent layer cannot be affected detrimentally. The caps 6, 1 and the tube holders l2, l5 may be so constructed according to a method frequently employed that the contact members 8, 9, l and H of the tube are placed laterally of the caps. In this case, the conductors 4 and may preferably be arranged on that side of the tube wall where the contact members are arranged so that they will be adjacent the wall. This case is shown in Figure 1a which is a cross-sectional view of the tube taken on the line AA.

The conductors 4 and 5 may also be arranged on the inner wall of the tube or in the tube wall. Under certain conditions a single conductor may suflice; on the other hand more than two conductors are required in certain circuit arrangements. These conductors must be connected to two contact members at different ends of the tube.

The presence of the conductors 4 and 5 on the tube wall has the additional advantage of assisting the ignition and these conductors also contribute to suppressing radio disturbances brought about bythe discharge.

Figure 2 shows a device in which all the series-connecting and operating elements are housed in the lamp-holders 3| and 32. The holder 3| contains a choke coil 33, a condenser 34, four contact members 35, 36, 31, 38 and current con,- ductors which terminate in connecting members 39 and 40. In this case, the connecting member 39 is connected to the contact member 35 and the connecting member 40 through the choke coil 33 to the contact member 36. The condenser 34 is arranged between the contact members '31 and38; v

"The holder 32 contains a choke coil'having two windings 4| and 42 and four contact members 43, 44, 45 and 4B. The winding 4| is connected to the contact members 45 and 46 and the wind- 4 ing 42 is connected to the contact members 43 and. 44.

The discharge tube 41, which for example may also be a low-pressure mercury vapour discharge tube, is provided at each end with a cap 48 or 49 respectively, with four contact members 50, 5|, 52 and 53 or 54, 55, 56 and 5'! respectively. These members act to make contact with the corresponding members of the lamp-holders. The contact members 5| and 52 or 55 and 56 have connected between them an incandescent electrode 58 or 59 of the discharge tube. The outer wall of this tube supports two conductors 60 and BI. The conductor 60 terminates in the contact members 50 and 54, whereas the conductor 6| is connected to the contact members 53 and 51.

On connection of the device to a source of alternating current a current passes through the conductor 60, the winding 42, the electrode 59, the winding 4!, the conductor 6|, the condenser 34, the electrode 53 and the choke coil 33. Owing to the fact that the choke coil windings H and 42 are wound in such manner that the resulting magnetic field is very feeble and the choke coil 33 and the condenser 34 are so proportioned that their resistance values are substantially identical, the said current is very high and a high resonance voltage occurs between the electrodes of the lamp. The electrodes 58 and 59 are thus rapidly heated and the tube is started up under the action of the said high voltage between the electrodes, after which the current strength goes down to the ordinary operating value.

Again, if the tube is removed, one of the lampholders, that is to say the holder 32, is. not connected to the source of current supply so that there is no need to house conductors in the wall or in an insulating tube between the widely spaced lamp-holders. In this case, the conductors 6D and 6!, each of which is connected to two contact members placed at difierent ends of the tube are insulated with respect to the two electrodes of the tube.

WhatIclaim is:

1. In combination, a pair of spaced lamp holders one of which is provided with a pair of contacts and a pair of terminals for connection to a power source, each of said contacts connecting to one of said terminals, and the other of which includes a pair of contacts and a starting switch connected across said contacts, the said other holder being free from terminals for connection to the power source, and an elongated gaseous electric discharge lamp having an elongated envelope mounted in said holders and comprising at each end an electrode of the preheated type and a pair of contact prongs extending lon gitudinally from each end of the lamp engage able with respective contacts of one of the lamp holders and one of which prongs is electrically connected to one end of the adjacent electrode and the other of which prongs is free of such connection, and a pair of conductors integral with and extending along the envelope and each being connected to the free prong at one end of the lamp and to the free end of the electrode at the opposite end of the lamp whereby the lamp is properly connected electrically in any position in which it may be inserted in said lamp holders and said starting switch is electrically connected through said conductors for effecting starting and operation of the lamp.

2. In combination, a pair of spaced lamp holders and an elongated gaseous electric discharge lamp having 4 an elongated envelope mounted in said holders and comprising at each end an electrode of the preheated type and two pairs of contact prongs extending longitudinally from each end of the lamp, and a pair of conductors integral with and extending along the envelope, one of said lamp holders being provided with two pairs of contacts engageable with the contact prongs on the end of the lamp. and one pair of terminals, one pair of contacts connecting through a choke to the pair of terminals for connection to a power source, the other pair of contacts being connected together through a capacitor, the other lamp holder being provided with two pairs of contacts, each pair being connected together through a separate choke, one contact of each pair on each lamp holder engaging a corresponding contact prong on the lamp connecting to the electrode in the lamp, the other contact of each pair connecting to a corresponding contact prong on the lamp which is connected to the corresponding contact prong at the other end 01 the lamp through one of the conductors on the envelope, whereby the lamp 6 is properly connected electrically in either position in which it may be inserted in said lamp holders and the chokes and capacitor are properly interconnected for effecting starting and operation of the lamp.

ERNO MANN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 706,314 Gilmore Aug. 5, 1902 2,056,635 Wiegand Oct. 6, 1936 2,273,960 Hopkins Feb. 24, 1942 2,276,829 De Reamer Mar. 17, 1942 2,298,336 Babb Oct. 13, 1942 2,301,670 Abadie Nov. 10, 1942 2,337,745 Garstang Dec. 28, 1943 2,344,122 Bay Mar. 14, 1944 2,369,123 Abshire Feb. 13, 1945 2,448,937 Walter Sept. 7, 1948 

